Add MediaStreamSource frame rate calculation to the tracker.

content/browser/media/webrtc_internals.h

Index: content/browser/media/webrtc_internals.h
diff --git a/content/browser/media/webrtc_internals.h b/content/browser/media/webrtc_internals.h
index 241b147e527027e378da6aee4a5938b4ff7a7810..c39bfd1abb626f0ddc9d766ab7a86448fce6801e 100644
--- a/content/browser/media/webrtc_internals.h
+++ b/content/browser/media/webrtc_internals.h
@@ -80,6 +80,11 @@ class CONTENT_EXPORT WebRTCInternals : public NotificationObserver,
                       const std::string& audio_constraints,
                       const std::string& video_constraints);
 
+  void OnAddVideoStats(base::ProcessId pid,
+                       const std::string& video_id,
+                       float input_frame_rate,
+                       int number_of_dropped_frames);
+
   // Methods for adding or removing WebRTCInternalsUIObserver.
   void AddObserver(WebRTCInternalsUIObserver *observer);
   void RemoveObserver(WebRTCInternalsUIObserver *observer);